LIQUID METAL EJECTOR BUOYANT SENSING SYSTEM AND METHODS THEREOF
A metal ejecting apparatus is disclosed. The metal ejecting apparatus includes a nozzle orifice in connection with the inner cavity and configured to eject one or more droplets of the liquid metal printing material, a float in contact with a surface of the liquid metal printing material, where the float is buoyant within the liquid printing material, and a filament attached to the float on a first end and attached to a level sensing system on a second end. The level sensing system may include an ultrasonic sensor, a visual sensor, a mechanical force sensor, a laser sensor, or a combination thereof. A method of sensing and controlling a level of liquid printing material in a metal jetting apparatus is also disclosed.
1 . A metal ejecting apparatus, comprising:
a structure defining an inner cavity to contain a liquid metal printing material;
a nozzle orifice in connection with the inner cavity and configured to eject one or more droplets of the liquid metal printing material;
a float in contact with a surface of the liquid metal printing material, wherein the float is buoyant within the liquid printing material; and
a filament attached to the float on a first end and attached to a level sensing system on a second end.
2 . The metal ejecting apparatus of claim 1 , wherein the float is hollow.
3 . The metal ejecting apparatus of claim 1 , wherein a density of the float is less than a density of the liquid metal printing material.
4 . The metal ejecting apparatus of claim 1 , wherein the float comprises boron nitride.
5 . The metal ejecting apparatus of claim 1 , wherein the float is non-wetting when in contact with the liquid metal printing material.
6 . The metal ejecting apparatus of claim 1 , wherein the float is resistant to high temperature.
7 . The metal ejecting apparatus of claim 1 , wherein the filament is under tension.
8 . The metal ejecting apparatus of claim 1 , wherein the filament comprises a material that is resistant to high temperature and non-wetting when in contact with the liquid metal printing material.
9 . The metal ejecting apparatus of claim 1 , wherein the filament comprises an indicating feature in one or more locations along a length of the filament.
10 . The metal ejecting apparatus of claim 9 , wherein the indicating feature is configured to alert the level sensing system of a low level of liquid metal printing material.
11 . The metal ejecting apparatus of claim 9 , wherein the indicating feature is configured to alert the level sensing system of a sufficient level of liquid metal printing material.
12 . The metal ejecting apparatus of claim 1 , wherein the level sensing system comprises an ultrasonic sensor, a visual sensor, a mechanical force sensor, a laser sensor, or a combination thereof.
13 . A metal ejecting apparatus, comprising:
a structure defining an inner cavity to contain a liquid metal printing material;
a nozzle orifice in connection with the inner cavity and configured to eject one or more droplets of the liquid metal printing material;
a float in contact with a surface of the liquid metal printing material wherein the float is buoyant within the liquid printing material;
a filament comprising an indicating feature, attached to the float on a first end, and attached to a level sensing system; and
wherein the level sensing system is configured to receive a signal from the indicating feature.
14 . The metal ejecting apparatus of claim 13 , wherein:
the indicating feature is configured to alert the level sensing system of a low level of liquid metal printing material; and
the indicating feature is configured to alert the level sensing system of a sufficient level of liquid metal printing material.
15 . The metal ejecting apparatus of claim 13 , wherein the level sensing system comprises an ultrasonic sensor, a visual sensor, a mechanical force sensor, a laser sensor, or a combination thereof.
16 . A method of sensing and controlling a level of liquid printing material in a metal jetting apparatus, comprising:
placing a buoyant float onto a surface of a liquid printing material held within an inner cavity of the metal jetting apparatus;
receiving a first signal indicative of a vertical position of the buoyant float within the inner cavity of the metal jetting apparatus; and
sending a second signal to a printing material feed system.
17 . The method of sensing and controlling a level of liquid printing material in a metal jetting apparatus of claim 16 , wherein receiving the first signal is completed with a level sensing system comprising an ultrasonic sensor, a visual sensor, a mechanical force sensor, a laser sensor, or a combination thereof.
18 . The method of sensing and controlling a level of liquid printing material in a metal jetting apparatus of claim 16 , further comprising adding printing material from the printing material feed system when the first signal indicates that the vertical position of the buoyant float denotes an insufficient level of liquid printing material held within the inner cavity of the metal jetting apparatus.
19 . The method of sensing and controlling a level of liquid printing material in a metal jetting apparatus of claim 16 , further comprising stopping an addition of printing material from the printing material feed system when the first signal indicates that the vertical position of the buoyant float denotes a sufficient level of liquid printing material held within the inner cavity of the metal jetting apparatus.
20 . The method of sensing and controlling a level of liquid printing material in a metal jetting apparatus of claim 16 , further comprising heating a solid printing material held within the inner cavity of the metal ejecting apparatus, thereby causing the solid printing material held to change to a liquid within the metal ejecting apparatus.